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1 online resource (p. 2825–2831 ) : digital, PDF file.
<sup>13</sup>C-Metabolic Flux Analysis (<sup>13</sup>C-MFA) is rapidly being recognized as the authoritative method for determining fluxes through metabolic networks. Site-specific <sup>13</sup>C enrichment information obtained using NMR spectroscopy is a valuable input for <sup>13</sup>C-MFA experiments. Chemical shift overlaps in the 1D or 2D NMR experiments typically used for <sup>13</sup>C-MFA frequently hinder assignment and quantitation of site-specific <sup>13</sup>C enrichment. Here we propose the use of a 3D TOCSY-HSQC experiment for <sup>13</sup>C-MFA. We employ Non-Uniform Sampling (NUS) to reduce the acquisition time of the experiment to a few hours, making it practical for use in <sup>13</sup>C-MFA experiments. Our data show that the NUS experiment is linear and quantitative. Identification of metabolites in complex mixtures, such as a biomass hydrolysate, is simplified by virtue of the <sup>13</sup>C chemical shift obtained in the experiment. In addition, the experiment reports <sup>13</sup>C-labeling information that reveals the position specific labeling of subsets of isotopomers. As a result, the information provided by this technique will enable more accurate estimation of metabolic fluxes in larger metabolic networks.
1 online resource (11 p. ) : digital, PDF file.
This is a Laboratory Analytical Procedure (LAP) for bio-oil analysis.
1 online resource (12 p. ) : digital, PDF file.
In this study, the Fischer-Tropsch synthesis (FTS) reaction is one of the most promising processes to convert alternative energy sources, such as natural gas, coal or biomass, into liquid fuels and other high-value products. Despite its commercial implementation, we still lack fundamental insights into the various deactivation processes taking place during FTS. In this work, a combination of three methods for studying single catalyst particles at different length scales has been developed and applied to study the deactivation of Co/TiO<sub>2</sub> Fischer-Tropsch synthesis (FTS) catalysts. By combining transmission X-ray microscopy (TXM), scanning transmission X-ray microscopy (STXM) and scanning transmission electron microscopy-electron energy loss spectroscopy (STEM-EELS) we visualized changes in the structure, aggregate size and distribution of supported Co nanoparticles that occur during FTS. At the microscale, Co nanoparticle aggregates are transported over several μm leading to a more homogeneous Co distribution, while at the nanoscale Co forms a thin layer of ~1-2 nm around the TiO<sub>2</sub> support. The formation of the Co layer is the opposite case to the “classical” strong metal-support interaction (SMSI) in which TiO<sub>2</sub> surrounds the Co, and is possibly related to the surface oxidation of Co metal nanoparticles in combination with coke formation. In other words, the observed migration and formation of a thin CoO<sub>x</sub> layer are similar to a previously discussed reaction-induced spreading of metal oxides across a TiO<sub>2</sub> surface.
1 online resource.
  • Employing 'second generation' matrices.- (MA)LDI MS mass spectrometry imaging at high specificity and sensitivity.- Techniques for fingermark analysis using MALDI MS - a practical overview.- Whole/Intact Cell MALDI MS Biotyping in Mammalian Cell Analyis.- MALDI biotyping for microorganism identification in clinical microbiology.- Future applications of MALDI-TOF MS in microbiology.- MALDESI: Fundamentals, direct analysis, and MS imaging.- Microprobe MS Imaging of Live Tissues, Cells, and Bacterial Colonies using LAESI.- Efficient production of multiply charged MALDI ions.- Food Authentication by MALDI MS - MALDI-TOF MS Analysis of Fish Species.- Quantitative MALDI MS using Ionic Liquid Matrices.- Disease profiling by MALDI MS analysis of biofluids.- Ionic Liquids and other liquid matrices for sensitive MALDI MS analysis.- Coupling liquid MALDI MS to liquid chromatography.
  • (source: Nielsen Book Data)9783319048185 20160619
This book covers the state-of-the-art of modern MALDI (matrix-assisted laser desorption/ionization) and its applications. New applications and improvements in the MALDI field such as biotyping, clinical diagnosis, forensic imaging, and ESI-like ion production are covered in detail. Additional topics include MS imaging, biotyping/speciation and large-scale, high-speed MS sample profiling, new methods based on MALDI or MALDI-like sample preparations, and the advantages of ESI to MALDI MS analysis. This is an ideal book for graduate students and researchers in the field of bioanalytical sciences. This book also: * Showcases new techniques and applications in MALDI MS * Demonstrates how MALDI is preferable to ESI (electrospray ionization) * Illustrates the pros and cons associated with biomarker discovery studies in clinical proteomics and the various application areas, such as cancer proteomics.
(source: Nielsen Book Data)9783319048185 20160619
The current invention describes methods and compositions of various sorbents based on aerogels of various silanes and their use as sorbent for carbon dioxide. Methods further provide for optimizing the compositions to increase the stability of the sorbents for prolonged use as carbon dioxide capture matrices.
Systems for converting aldose sugars to ketose sugars and separating and/or concentrating these sugars using differences in the sugars' abilities to bind to specific affinity ligands are described.
1 online resource (3 p. ) : digital, PDF file.
This report documents a Pu isotopic analysis.
1 online resource (15 p. ) : digital, PDF file.
The degradation of Antifoam 747 to form flammable decomposition products has resulted in declaration of a Potential Inadequacy in the Safety Analysis (PISA) for the Defense Waste Processing Facility (DWPF). Savannah River National Laboratory (SRNL) testing with simulants showed that hexamethyldisiloxane (HMDSO), trimethylsilanol (TMS), and 1-propanal are formed in the offgas from the decomposition of the antifoam. A total of ten DWPF condensate samples from Batch 735 and 736 were analyzed by SRNL for three degradation products and additional analytes. All of the samples were analyzed to determine the concentrations of HMDSO, TMS, and propanal. The results of the organic analysis found concentrations for propanal and HMDSO near or below the detection limits for the analysis. The TMS concentrations ranged from below detection to 11 mg/L. The samples from Batch 736 were also analyzed for formate and oxalate anions, total organic carbon, and aluminum, iron, manganese, and silicon. Most of the samples contained low levels of formate and therefore low levels of organic carbon. These two values for each sample show reasonable agreement in most cases. Low levels of all the metals (Al, Fe, Mn, and Si) were present in most of the samples.
1 online resource (26 p. ) : digital, PDF file.
The Bioenergy Program at Pacific Northwest National Laboratory (PNNL) is evaluating the feasibility of converting wastewater sludge materials to fuels. Wastewater sludge from various municipalities will be used in the evaluation process and as with any municipal waste, there is the potential for residual contaminates to remain in the sludge following wastewater treatment. Many surveys and studies have confirmed the presence of pharmaceuticals in municipal wastewater and effluents (World Health Organization, 2011). Determination of the presence and concentrations of the contaminants is required to define the proper handling of this sludge. A list of targeted compounds was acquired from the literature and an analytical method was developed for the pharmaceutical and personal care compounds. The presence of organics complicated the analytical techniques and, in some cases, the precision of the results. However, residual concentrations of a range of compounds were detected in the wastewater sludge and the presence and concentrations of these compounds will be considered in identifying the appropriate handling of this material in conduct of research.
1 online resource (9 p. ) : digital, PDF file.
LANL has been contacted to provide possible assistance in safe disposition of a number of <sup>241</sup>Am-bearing materials associated with local industrial operations. Among the materials are ion exchange resins which have been in contact with <sup>241</sup>Am and nitric acid, and which might have potential for exothermic reaction. The purpose of this paper is to analyze and define the resin forms and quantities to the extent possible from available data to allow better bounding of the potential reactivity hazard of the resin materials. An additional purpose is to recommend handling procedures to minimize the probability of an uncontrolled exothermic reaction.
1 online resource (16 p. ) : digital, PDF file.
Savannah River National Laboratory analyzed samples from Tank 38H and Tank 43H to support Enrichment Control Program and Corrosion Control Program. The total uranium in the Tank 38H samples ranged from 20.5 to 34.0 mg/L while the Tank 43H samples ranged from 47.6 to 50.6 mg/L. The U-235 percentage ranged from 0.62% to 0.64% over the four samples. The total uranium and percent U-235 results appear consistent with previous Tank 38H and Tank 43H uranium measurements. The Tank 38H plutonium results show a large difference between the surface and sub-surface sample concentrations and a somewhat higher concentration than previous sub-surface samples. The two Tank 43H samples show similar plutonium concentrations and are within the range of values measured on previous samples. The plutonium results may be biased high due to the presence of plutonium contamination in the blank samples from the cell sample preparations. The four samples analyzed show silicon concentrations ranging from 47.9 to 105 mg/L.
1 online resource.
115 pages : illustrations ; 23 cm
A volume in the Emerging Issues in Analytical Chemistry series, published in partnership with RTI International and edited by Brian F. Thomas, The Analytical Chemistry of Cannabis: Quality Assessment, Assurance, and Regulation of Medicinal Marijuana and Cannabinoid Preparations provides analytical chemistry methods that address the latest issues surrounding cannabis-based products. The plethora of marketed strains of cannabis and cannabinoid-containing products, combined with the lack of industry standards and labelling requirements, adds to the general perception of poor quality control and limited product oversight. The methods described in this leading-edge volume help to support the manufacturing, labelling, and distribution of safe and consistent products with known chemical content and demonstrated performance characteristics. It treats analytical chemistry within the context of the diverse issues surrounding medicinal and recreational cannabis in a manner designed to foster understanding and rational perspective in non-scientist stakeholders as well as scientists who are concerned with bringing a necessary degree of order to a field now characterized by confusion and contradiction. * Addresses current and emerging analytical chemistry methods-an approach that is unique among the literature on this topic* Presents information from a broad perspective of the issues in a single compact volume* Employs language comprehensible to non-technical stakeholders as well as to specialists in analytical chemistry.
(source: Nielsen Book Data)9780128046463 20160619
Biology Library (Falconer)
1 online resource (5 volumes) : illustrations (some color)
  • Volume 1. Liquid chromatography
  • volume 2. Special liquid chromatography modes and capillary electromigration techniques
  • volume 3. Gas, supercritical and chiral chromatography
  • volume 4. Chromatographic and related techniques
  • volume 5. Sample treatment, method validation, and applications.
The disclosure discloses abrasion resistant, persistently hydrophobic and oleophobic, anti-reflective and anti-soiling coatings for glass. The coatings described herein have wide application, including for example the front cover glass of solar modules. Methods of applying the coatings using various apparatus are disclosed. Methods for using the coatings in solar energy generation plants to achieve greater energy yield and reduced operations costs are disclosed. Coating materials are formed by combinations of hydrolyzed silane-base precursors through sol-gel processes. Several methods of synthesis and formulation of coating materials are disclosed.
1 online resource (viii, 336 pages) : illustrations (some color)
In the last quarter century, advances in mass spectrometry (MS) have been at the forefront of efforts to map complex biological systems including the human metabolome, proteome, and microbiome. All of these developments have allowed MS to become a well-established molecular level technology for microbial characterization. MS has demonstrated its considerable advantage as a rapid, accurate, and cost-effective method for microbial identification, compared to conventional phenotypic techniques. In the last several years, applications of MS for microbial characterization in research, clinical microbiology, counter-bioterrorism, food safety, and environmental monitoring have been documented in thousands of publications. Regulatory bodies in Europe, the US, and elsewhere have approved MS-based assays for infectious disease diagnostics. As of mid-2015, more than 3300 commercial MS systems for microbial identification have been deployed worldwide in hospitals and clinical labs. While previous work has covered broader approaches in using MS to characterize microorganisms at the species level or above, this book focuses on strain-level and subtyping applications. In thirteen individual chapters, innovators, leaders and practitioners in the field from around the world have contributed to a comprehensive overview of current and next-generation approaches for MS-based microbial characterization at the subspecies and strain levels. Chapters include up-to-date reference lists as well as web-links to databases, recommended software, and other useful tools. The emergence of new, antibiotic-resistant strains of human or animal pathogens is of extraordinary concern not only to the scientific and medical communities, but to the general public as well. Developments of novel MS-based assays for rapid identification of strains of antibiotic-resistant microorganisms are reviewed in the book as well. Microbiologists, bioanalytical scientists, infectious disease specialists, clinical laboratory and public health practitioners as well as researchers in universities, hospitals, government labs, and the pharmaceutical and biotechnology industries will find this book to be a timely and valuable resource.
The invention provides methods and compositions useful for synthesizing alkylaromatics from an n-alkanes.
Compound of Formula I: are described, along with compositions containing the same and methods of use thereof. ##STR00001##
A novel electron acceptor based on bay-annulated indigo (BAI) was synthesized and used for the preparation of a series of high performance donor-acceptor small molecules and polymers. The resulting materials possess low-lying LUMO energy level and small HOMO-LUMO gaps, while their films exhibited high crystallinity upon thermal treatment, commensurate with high field effect mobilities and ambipolar transfer characteristics.
1 online resource (p. 2162-2170 ) : digital, PDF file.

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